This application discloses a transmission method, a transmission apparatus, and a communications device. The transmission method includes: performing polar polar encoding on a bit sequence, to obtain an encoded sequence, where the bit sequence includes control information and a cyclic redundancy check CRC sequence; fragmenting the encoded sequence, to obtain n encoded subsequences, where n is an integer, and n>0; and scrambling the n encoded subsequences by using n scrambling sequences respectively, to obtain n scrambled sequences. In the transmission method, the n scrambling sequences are newly defined based on encoding and decoding features of a polar code, and the n scrambling sequences additionally carry ┌log 2 n┐ -bit information. According to the foregoing encoding method, signaling overheads are reduced.